Radio frequency (RF) high power communications units in a satellite communications system typically have maximum power limits. If the maximum power limit is exceeded, the power unit may be damaged. The maximum power limit can be divided into an instantaneous power limit and a specific time window average power limit. Typically, a power unit has a different limit to instantaneous power level and to average power levels. The power unit loading typically varies with traffic loading in the system. Accordingly, the more traffic or communications signals being carried by the satellite or spacecraft, the higher the signal power being carried or transmitted through the power units of the satellite. The power unit overload problems are a major concern to a satellite communications system, especially to a ground beam forming communications systems. Current industry practice is to provide a substantial power margin to the power units with no active power management in the system, especially for the average power limit. However, if a power unit is overloaded, the unit may be damaged. There are some existing protection schemes available in practice, which use hardware limitation (such as amplifiers) to limit certain unit output power. However, these schemes typically can only limit the instantaneous maximum power. Such schemes are not useable with any beam forming techniques or in a beam forming environment.